content: /*
   * Copyright 2011-2016 David Karnok
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package ix;
  
  import java.util.Iterator;
  import java.util.concurrent.Callable;
  
  final class IxFlattenArrayIterable<T> extends Ix<T> {
  
      final Iterable<T>[] sources;
  
      IxFlattenArrayIterable(Iterable<T>[] sources) {
          this.sources = sources;
      }
  
      @Override
      public Iterator<T> iterator() {
          return new FlattenIterator<T>(sources);
      }
  
      static final class FlattenIterator<T> extends IxBaseIterator<T> {
  
          final Iterable<T>[] sources;
  
          Iterator<? extends T> current;
  
          int index;
  
          FlattenIterator(Iterable<T>[] sources) {
              this.sources = sources;
          }
  
          @SuppressWarnings("unchecked")
          @Override
          protected boolean moveNext() {
              Iterator<? extends T> c = current;
  
              while (c == null) {
                  int i = index;
                  if (i != sources.length) {
                      Iterable<? extends T> inner = sources[i];
                      index = i + 1;
                      if (inner instanceof Callable) {
                          value = checkedCall(((Callable<T>)inner));
                          hasValue = true;
                          return true;
                      }
  
                      c = inner.iterator();
  
                      if (c.hasNext()) {
                          current = c;
                          break;
                      } else {
                          c = null;
                      }
                  } else {
                      done = true;
                      return false;
                  }
              }
  
              value = c.next();
              hasValue = true;
  
              if (!c.hasNext()) {
                  current = null;
              }
              return true;
          }
  
      }
  
  }
  